Spring energized fastening tools include staple guns, nailers, desktop staplers and other such devices where storing and releasing energy to install a fastener is by impact blow. Other examples of such devices include, but are not limited to, using spring energy storage in marking tools where a mark or dent is placed in a work piece. In spring energized devices, a handle, lever or other movable member is moved to deflect a spring and store energy to be used on a driving piece. At a predetermined or selected point of operation, a holding member is released from the driving piece to allow the driving piece to move under the force of the deflected spring. This releasing action on the holding member occurs over a small portion of normal motion of the handle, lever or energy input device. The releasing action may require additional handle force that becomes concentrated at the small portion of motion. This will increase the peak force a user must exert on the handle, lever or equivalent structure.